# If f(x)= 2x sin(x) cos(x), how do you find f'(x)?

##### 1 Answer

May 15, 2015

Alternative answer:

Use trigonometry (sine of 2x) to rewrite the function first:

Now use the product rule and use the chain rule to get:

Simpply to get:

I know it doesn't look the same as the other answer. Use trigonometric identities to see that the answers are equivalent.